My single-posts page is missing the sidebar

I am working on a site I do not own so please ignore the message about not offering a site link. The site for this discussion is here: <http://blog.homeexchange.com/&gt;

I am customizing the 2011 theme and I am using the CSS customization editor.

The home page displays content within a "primary" div on the left and the sidebar displays on the right in a "secondary" div. But when I click the About link <http://blog.homeexchange.com/about/&gt; Not only is the sidebar missing. I don't see a 'secondary' div when I view the page with Firebug.

What's more is that if I click on either post from the home page example <http://blog.homeexchange.com/2011/07/07/15/&gt; the sidebar is missing on them too. I cannot find a way to select to display a sidebar and I don't see where it might be turned off. And if I saw that the secondary div even existed I would force the div to "display: block". But the div doesn't seem to exist.

Please post an active link starting with http:// to the blog in question
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